President Donald Trump declared in executive orders this month that the federal government would try to “reduce crime in America” and that the White House was opposed to violence against law enforcement officers.

Our criminal justice system works mostly at the local and state level, so the executive branch of the federal government is limited in its influence over local police. Crime reduction does not happen through fearmongering or federal fiat. And violence against police is illegal. But although the substance of these orders is near zero, their very existence reveals a shift in focus under the Trump White House.

Reducing crime is a fabulous wish, and a federal focus on crime reduction was absent in the previous administration. But Trump has little knowledge of the issues at hand. His rhetoric about the perils of cities — which relied on false statements about murder rates — illustrates that the devil, as always, is in the details.

Trump declares himself to be a “law-and-order” president. Although very few people are against either law or order, the phrase has a uniquely right-wing and racist history, one that Trump has been quick to exploit. “Law and order,” one executive order states, requires a focus on “illegal immigration, drug trafficking and violent crime.” This misunderstands the nature of crime in America.

Trump’s finger-pointing at immigrants — Mexicans and Muslims in particular — is particularly misguided, since these groups have little to do with crime or violence in America. Immigrants, no matter their religion or legal status, commit violence at lower rates than native-born Americans. One reason New York City has bucked a national trend and not seen a recent increase in violent crime is one in three New Yorkers — more than 3 million people, including many undocumented and hundreds of thousands of Muslims — are foreign-born. Also contrary to the national trend, New York brought down crime while reducing incarceration.

Certainly Trump’s bombast on crime marks a departure from former President Obama’s administration, which called for a more holistic approach to crime prevention. To reduce racial disparities in policing, an Obama task force encouraged less aggressive policing . Obama’s Justice Department gave short shrift to the role of police in crime prevention and focused almost exclusively on police misconduct. Under Trump and Attorney General Jeff Sessions, it’s almost guaranteed that federal investigations of police departments, much less individual officers, will end. Whether this shift in focus is good or bad remains to be seen.

Trump is correct when he states that violence in America has recently increased. Crime is still much lower than it was 10, 20 or even 50 years ago. Statements to the contrary are lies. But the past two years have seen an unprecedented homicide increase, close to 25 percent nationwide. (Official 2016 data won’t be released by the FBI until later this year.) Although not every city has seen an increase — and a few cities, Chicago in particular, have seen an even greater increase — the overall nationwide increase is large, worrisome and disproportionately impacts nonwhites. African Americans now constitute the majority of America’s murder victims.

Also in 2016, the number of police officers killed on duty increased by a third, bucking a downward trend that has persisted since the early 1970s. Last year 64 cops were shot and killed, the most since 2011. Many police officers and others on the political right were quick to blame anti-police protesters and Obama. Although that is simplistic — even jingoistic, and often misguided on the facts — it’s a very deeply rooted belief.

The vast majority of police officers — 86 percent, according to a Pew Research survey — say high-profile incidents have made their job more difficult, and 93 percent say officers in their department have become more concerned about their safety. Three of four officers say their colleagues are more reluctant to stop people who seem suspicious or use force when appropriate. Whether at a local or national level, politics and protests have not made policing easier or reduced crime. Whether police abuses have decreased or not is unknown.

Chicago, which Trump has called out in particular for unacceptable levels of violence, has documented cases of individual and institutional police misconduct. Last year — partly in response to scandals and outside pressure — arrests, complaints and even police-involved shootings in Chicago decreased. But homicides rose in sync, because nowhere in the police-are-the-problem narrative is there any clear and effective vision as to how police should confront criminals and deter crime. The answer to bad policing is better policing, not less policing.

That’s not to say protests and a focus on bad policing haven’t shed light on real problems. There is still no national database of police-involved shootings and use of force. And too many towns continue to see police enforcement and the court system primarily as a “revenue stream” to fund municipal government.

Perhaps Trump’s two executive orders will end up being little more than a kind word to cops, a form of thanks to those who put their life on the line for strangers. Such appreciation — simply acknowledging that police tend to be on the side of good — isn’t such a bad thing. Obama, in a funeral speech in Dallas for murdered police officers, compared the suffering of families of those killed by police to the suffering of the families of the fallen cops. While that’s true at a human level, perhaps a police funeral isn’t the right time to stake a nuanced position of moral equivalence. Certainly it did nothing to endear Obama to the rank and file.

Any profession, law enforcement included, appreciates kind words from up top. But the White House has to be more than a pulpit for a bully. Ultimately Trump will be judged by deeds, not words. And the president’s actions are not promising. Border restrictions and immigrant raids do more harm than good, and neither does anything to reduce the “carnage” of urban violence over which Trump professes concern. Ramping up the war on drugs, with its multi-decade track record of futility, is certainly not the answer. Nor is increased incarceration, particularly when private prisons are involved. This is where the president’s power could do serious national harm.

Crime reduction does not happen through “zero tolerance,” xenophobia or any slogan that can fit on a bumper sticker. Crime, violent crime especially, is related to society’s problems: illegal guns, lack of mental-health care, segregation, unemployment, drug prohibition and a general erosion of family, social and civic structure. These all desperately need our attention.

Policing is not one-size-fits-all, but we have a pretty good idea of what works and what doesn’t. Repeat violent offenders, particularly in cases involving illegal guns, need special attention and formal prosecution. When it comes to minor crimes and quality-of-life issues, though, residents must help identify problems and potential solutions. Police should help residents maintain order. Proactive policing, especially when it disproportionately affects minorities in high-crime areas, requires constant communication. A top-down approach of arrests and imprisonment does little but create justifiable resentment.

A free, diverse and civic society depends on good policing. If law enforcement shifts its focus to “cracking down” on immigrants, Muslims or any other enemy Trump invents, we risk a descent into repression and crime.

Peter Moskos, the author of “Cop in the Hood” and a former Baltimore police officer, is an associate professor at John Jay College of Criminal Justice.

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